Integrated circuits may include a plurality of different semiconductor devices integrated in a semiconductor body. A failure, such as a short-circuit external to the integrated circuit, may cause electrical energy to be dissipated in one or in several of these devices in the semiconductor body and may, therefore, cause the temperature of the semiconductor body to increase. At the beginning, which is right after the failure occurs, the temperature increase is only local, namely at the position where the dissipating semiconductor device is located, while the region with the increased temperature expands when the failure is present for a longer time. In order to prevent the integrated circuit from being thermally overloaded at least one temperature sensor can be arranged in the integrated circuit. This temperature sensor provides a temperature signal that is representative of a temperature at the position where the temperature sensor is located. This temperature is evaluated, so as to be able to take suitable over temperature protection measures, such as switching off a part of the integrated circuit.
According to one approach, not only the temperature at one position, but also a temperature difference between the temperatures at two positions is measured and evaluated.
In integrated circuits with a plurality of different devices and a plurality of temperature sensors an evaluation circuit that is configured to evaluate the individual temperatures or temperature differences can be quite complex.
There is a need for a temperature evaluation circuit that is easy to implement and that can be easily adapted to specific needs.